Pranksters are plastering Manhattan with bogus posters showing police attacking the city with missiles fired from a drone.

“NYPD Drones. Protection when you least expect it,” read the posters, which show a black plane dropping a white missile on a fleeing family. The signs bear imitation NYPD and Ad Council logos.

The vandals somehow open the plastic shields protecting genuine ads on phone booths and stick the bogus notices in front of them.

NYPD spokesman Paul Browne quipped, “I can tell you they didn’t pay for the space.’’

The phony ads were spotted near the Staten Island Ferry Terminal and in Chelsea one day after Occupy Wall Street protesters returned to the city to celebrate its first anniversary. But it was not known who was behind the poster prank.

Annie Cohart, 25, an elementary school teacher, was not amused. “It’s a little scary to me, the missile chasing after the kid, at a quick glance it’s unsettling,” she said.

A 30-year-old Chelsea man, who asked not to be identified, said, “It looks real, there are NYPD posters in the subway that look just like them.”

Similar posters were spotted earlier this summer, and, in April, two signs stating “Attention Drone Activity in Progress NYPD” were erected outside the Museum of Natural History and Lincoln Center.